Apparatus and Method for Removing Amalgam and Waste Particles From Dental Office Suction Effluent

ABSTRACT

An apparatus and method for removing amalgam and waste particles from dental office suction effluent. The apparatus includes an upper chamber and a solids collection canister removably secured thereto. Dental office suction effluent drawn through a dental suction wand enters the upper chamber along a lateral flow path above a substantially cylindrical internal wall portion. A gas component of dental office suction effluent changes direction by more than 60° before it exits the upper chamber through an exit port. A riser conveys a liquid and solids component of dental office suction effluent through a drain into the solids collection canister. A flow restrictor allows liquids and gases to exit the solids collection canister interior volume but prohibits solids from exiting the solids collection canister interior volume.

BACKGROUND OF INVENTION

This application is a continuation of U.S. application Ser. No.16/446,734, filed on Jun. 20, 2019, which claims priority to U.S.application Ser. No. 15/239,214, filed Aug. 17, 2016, now issued as U.S.Pat. No. 10,342,647, which claims priority to U.S. application Ser. No.14/519,959, filed Oct. 21, 2014, and claims priority to U.S. Prov.Patent App. Ser. No. 61/893,933, filed on Oct. 22, 2013, and U.S. Prov.Patent App. Ser. No. 62/013,019, filed on Jun. 17, 2014, all of whichare incorporated by reference herein in their entirety.

The present invention relates to an apparatus and a method for removingamalgam and waste particles from dental office suction effluent.

In dentistry and in the present specification, the term “amalgam”generally refers to the alloys of mercury and other metals such assilver, tin, copper, which are used to form dental restorative materials(e.g., fillings). Amalgam was the restorative material of choice formany years due to its relatively low cost, ease of application, strengthand durability. However, it has become less popular due to concerns overthe toxicity of mercury, which is the major component of amalgam, thedevelopment of alternative materials that are more aestheticallypleasing, and also due to concerns over environmental pollution.

Although amalgam is less frequently used for new dental fillings thanwas the case some decades ago, amalgam nevertheless continues tocomprise a significant portion of the metallic particle component ofdental office effluent. This is the case because when old fillingscomprising amalgam are drilled out and removed, amalgam particles areevacuated from the mouth as waste in such effluent. Furthermore, amalgamcontinues to be preferred for some tooth filling applications.

In addition to amalgam, dental office suction effluent includes saliva,rinsing fluid and solid particles such as aluminum oxides, which areused in abrasion treatments. It is important that the solid componentsof dental office suction effluent be separated from the liquid wastesbefore the latter are discharged into sanitary treatment systems.

The International Organization for Standardization (hereinafter “ISO”)has adopted a standard, which specifies the efficiency of amalgamseparators in terms of the level of retention of amalgam based on alaboratory test (ISO 11143:2008). And there are many amalgam separatorsavailable that comply with such standard.

One amalgam separator known in the art is sold by SolmeteX, Inc. ofNorthborough, Mass. under the trade designation HG5®. This deviceconsists of an upper chamber having two openings in an upper end and twoopenings in a lower end. One of the openings in the upper end is influid communication with a vacuum pump via piping, and the other openingin the upper end is in fluid communication with a dental suction wand. Acollection chamber is removably connected to the lower end of the upperchamber. Waste is drawn into the upper chamber through the dentalsuction wand with air drawn into the upper chamber by the vacuum pump.Liquids and solids in the dental suction effluent stream are separatedfrom the air to some degree in the upper chamber. The air flows out ofthe upper chamber to the vacuum pump. The liquids and solids flow underthe force of gravity through one of the openings in the lower end of theupper chamber and then through straight tubing into the collectionchamber. Solid particles settle and accumulate in the bottom of thecollection chamber. Liquid waste is drawn up through a filter thatextends into the collection chamber from the second opening in the lowerend of the upper chamber. This opening is in fluid communication with abypass conduit, which is connected to the piping to the vacuum pump.While the SolmeteX HG5® amalgam separator, and other similar products,are capable of separating amalgam and other solid particles from dentalwaste effluent streams, there is substantial room for improvement interms of collection capacity, separation efficiency and ease of use.

BRIEF SUMMARY OF THE INVENTION

In view of the foregoing, the present invention is directed toward anapparatus and method for removing amalgam and waste particles fromdental office suction effluent. The apparatus includes an upper chamberand a solids collection canister removably secured thereto. Dentaloffice suction effluent drawn through a dental suction wand enters theupper chamber along a lateral flow path above a substantiallycylindrical internal wall portion. A gas component of dental officesuction effluent changes direction by more than 60°. before it exits theupper chamber through an exit port. A riser conveys a liquid and solidscomponent of dental office suction effluent through a drain into thesolids collection canister. A flow restrictor allows liquids and gasesto exit the solids collection canister interior volume but prohibitssolids from exiting the solids collection canister interior volume.

According to one aspect, an apparatus for removing amalgam and wasteparticles from dental office suction effluent comprises an upper chamberhaving an upper end and a lower end, and a solids collection canisterremovably secured to the lower end of the upper chamber. The upperchamber includes an upper portion, a central portion having asubstantially cylindrical internal wall portion, and a lower portionhaving a basin portion. The upper portion, the central portion and thebasin portion of the lower portion cooperate to define an upper chamberinterior volume. An inlet provided in the upper portion of the upperchamber establishes a connection to an inlet line in fluid communicationwith at least one dental suction wand. An outlet provided in the lowerportion of the upper chamber establishes a connection to an outlet linein fluid communication with a vacuum pump. The solids collectioncanister includes a top portion and a bottom portion which togetherdefine a solids collection canister interior volume. The top portion ofthe solids collection canister is provided with a first opening and asecond opening. The first opening communicates with a drain provided inthe basin portion of the upper chamber, and the second openingcommunicates with the outlet. A riser communicates with the firstopening. The riser is adapted to convey liquids and solids of the dentaloffice suction effluent flowing from the upper chamber interior volumethrough the drain and the first opening to the bottom portion of thesolids collection canister. A flow restrictor communicates with thesecond opening. The flow restrictor is adapted to allow liquids andgases of the dental office suction effluent to exit the solidscollection canister interior volume but prohibit solids of the dentaloffice suction effluent from exiting the solids collection canisterinterior volume.

According to another aspect, an apparatus for removing amalgam and wasteparticles from dental office suction effluent comprises an upper chamberhaving an upper end, a lower end and a basin portion. The upper chamberdefines a longitudinal axis. A solids collection canister removablysecured to the lower end of the upper chamber. The solids collectioncanister includes a top portion provided with a first opening and asecond opening. The first opening communicates with a drain provided inthe basin portion of the upper chamber. An inlet is provided in theupper chamber for establishing a connection to an inlet line in fluidcommunication with at least one dental suction wand. The inlet is shapedand configured such that dental office suction effluent enters the upperchamber along a lateral flow path which is substantially perpendicularto the longitudinal axis of the upper chamber. An outlet is provided inthe upper chamber for establishing a connection to an outlet line influid communication with a vacuum pump. An exit port is provided in theupper chamber and communicates with the outlet. The exit port dischargesgases of dental office suction effluent entering the upper chamberthrough the inlet. A separate gas conduit is provided in the upperchamber and has a longitudinal axis substantially parallel to thelongitudinal axis of the upper chamber. The gas conduit communicateswith the exit port and the outlet for directing the discharged gasestoward the outlet. A flow restrictor is located in the solids collectioncanister. The flow restrictor is adapted to allow liquids and gases ofthe dental office suction effluent to exit the solids collectioncanister but prohibit at least about 99% by weight of solids of thedental office suction effluent that enter the solid collection canisterfrom exiting the solids collection canister.

According to yet another aspect, a method for removing amalgam and wasteparticles from dental office suction effluent comprises imparting acircular flow path to a dental office suction effluent entering an upperseparation chamber of a separation apparatus; separating gases from thedental office suction effluent and discharging the separated gases fromthe upper separation chamber; directing the dental office suctioneffluent into a solids collection canister removably secured to a lowerend of the upper chamber via a riser located in the solids collectioncanister; separating solids from the dental office suction effluent inthe solids collection canister; and discharging liquids and gases of thedental office suction effluent through a flow restrictor located in thesolids collection canister.

The foregoing and other features of the invention are hereinafter morefully described and particularly pointed out in the claims, thefollowing description setting forth in detail certain illustrativeembodiments of the invention, these being indicative, however, of but afew of the various ways in which the principles of the present inventionmay be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of an apparatus forremoving amalgam and waste particles from dental office suction effluentaccording to the present invention.

FIG. 2 is a partial section view of the upper portion of the apparatusshown in FIG. 1, which shows the primary flow path of dental officesuction effluent drawn into the apparatus.

FIG. 3 is a side section view taken through the middle of the apparatusshown in FIG. 1, which also shows the primary flow path of dental officesuction effluent drawn into the apparatus.

FIG. 4 is a perspective view of an upper chamber of the apparatus shownin FIG. 1, as viewed from the bottom.

FIG. 5 is a partial section view of a solids collection canister of theapparatus shown in FIG. 1.

FIGS. 6A-6D are perspective views of another embodiment of an apparatusfor removing amalgam and waste particles from dental office suctioneffluent according to the present invention.

FIG. 7 is a partial section view of the apparatus shown in FIG. 6B.

FIG. 8 is a section view through an upper portion of an upper chamber ofthe apparatus shown in FIG. 6A.

FIG. 9 is a section view of the apparatus shown in FIG. 6B.

DETAILED DESCRIPTION OF THE INVENTION

It should, of course, be understood that the description and drawingsherein are merely illustrative and that various modifications andchanges can be made in the structures disclosed without departing fromthe present disclosure. In general, the figures of the exemplaryapparatus for removing amalgam and waste particles from dental officesuction effluent are not to scale. It should be appreciated that theterm “plurality” means “two or more”, unless expressly specifiedotherwise. It will also be appreciated that the various identifiedcomponents of the exemplary apparatus disclosed herein are merely termsof art that may vary from one manufacturer to another and should not bedeemed to limit the present disclosure.

FIGS. 1-5 illustrate one embodiment of an apparatus 100 for removingamalgam and waste particles from dental office suction effluentaccording to the present invention. The apparatus 100 generallycomprises an upper chamber 102 having an upper end 104 and a lower end106, and a solids collection canister 110 removably secured to the lowerend 106 of the upper chamber 102. The upper chamber 102 includes anupper portion 120, a central portion 122 and a lower portion 124. Theupper portion 120 includes an outer wall portion 126 having a first wallportion 128 and a second wall portion 130 projecting outwardly from thefirst wall portion 128. According to one aspect, the first wall portion128 can be substantially hemispherical dome-shaped; although, this isnot required. A flange 134 extends about a periphery 136 of the outerwall 126. The flange 134 is shaped and configured to receive an upperpart 140 of the central portion 122, thereby securing the upper portion120 to the central portion 122. It should be appreciated that theconnection between the flange 134 of the upper portion 120 and thecentral portion 122 can be in the form of a sealed interference fitallowing for the removal of the upper portion 120 from the apparatus100. In the alternative, the connection between the flange 134 of theupper portion 120 and the central portion 122 can be in the form of apermanent connection via, for example, an adhesive and/or welding.

The central portion 122 includes an outer wall 142 defined by the upperpart 140 and a lower part 144. The upper and lower parts 140, 142 of thecentral portion 122 together define a substantially cylindrical internalwall portion 150, which in the depicted embodiment in an inner wallportion of the outer wall 142. The inner wall portion 150 is adapted toimpart a circular flow to the dental office suction effluent being drawninto the upper chamber 102. The lower portion 124 of the upper chamber102 includes a basin portion 156 defined by an outer wall 158 and abottom wall 160. Located about a periphery of an upper part 162 of theouter wall 158 is a flange 164 shaped and configured to receive thelower part 144 of the central portion 122, thereby securing the lowerportion 124 to the central portion 122. Again, it should be appreciatedthat the connection between the flange 164 of the lower portion 124 andthe central portion 122 can be in the form of a sealed interference fitallowing for the removal of the basin portion 156 from the apparatus100. In the alternative, the connection between the flange 164 of thelower portion 124 and the central portion 122 can be in the form of apermanent connection via, for example, an adhesive and/or welding. Asbetter illustrated in FIG. 3, the upper portion 120, the outer wall 142(i.e., the substantially cylindrical internal wall portion 150) of thecentral portion 122 and the basin portion 156 of the lower portion 124cooperate to define an upper chamber interior volume 170.

An inlet 180 is provided in the upper portion 120 of the upper chamber102 for establishing a connection to an inlet line (not shown) in fluidcommunication with at least one dental suction wand (not shown). Theinlet 180 is configured such that dental office suction effluent drawnthrough the at least one dental suction wand enters the upper portion120 of the upper chamber 102 along an initial lateral flow path into theupper portion 120 and then a circular flow path through the upperportion 120 above the internal wall portion 150 of the central portion122 (the lateral/circular flow path shown by arrows “A1” in FIGS. 1-3).The term “lateral” as used herein means that the flow path issubstantially sideways or horizontal (i.e., perpendicular) relative to alongitudinal axis defined by the upper chamber 102, and the term“circular” as used herein mean a flow path substantially around thelongitudinal axis of the upper chamber 102. It should be appreciatedthat the use of the substantially hemispherical domed-shaped first wallportion 128 of the upper portion outer wall 126 allows the incomingdental office suction effluent to quickly change direction as it entersthe upper portion 120 of the apparatus 100.

With reference to FIGS. 2 and 3, an exit port 186 is provided in theupper portion 120. The exit port 186 can be defined by the second wallportion 130 of the upper portion outer wall 126 together with aninternal divider 188 formed in the upper portion 120 to separate theinlet 180 from the exit port 186. As depicted, the divider 188 includesa cylindrical section 190 and a curved section 192 extending from thecylindrical section and into engagement with an interface of the firstand second wall portions 128, 130 adjacent the inlet 180. The first wallportion 128 together with the divider 188 define a circular flow pathfor the dental office suction effluent being drawn into the upperportion 120 of the upper chamber 102. According to one aspect, the exitport 186 is so arranged such that gases of dental office suctioneffluent entering the upper chamber 102 through the inlet 180 has tochange direction by more than at least 50°, and more preferably at least60°, before the gases can exit the upper chamber 102 through the exitport 186. In FIGS. 1-3, the primary flow of gases through the upperchamber 102 is illustrated using arrows “A2”. The dental office suctioneffluent is permitted to expand as it enters the upper portion 120 ofthe apparatus 100. The expansion and the change of flow direction in theupper portion 120 help separate gases from liquids and solids of thedental office suction effluent being drawn into the apparatus 100. Thedivider 188 defines an expansion/deceleration zone within the upperchamber interior volume 170, which further assists in separating liquidsand solids from the intake stream.

An outlet 200 is provided in the lower portion 124 for establishing aconnection to an outlet line (not shown) in fluid communication with avacuum pump (not shown). As best shown in FIGS. 1-3, the central portion122 includes a columnar portion 202 having a longitudinal axissubstantially parallel to the longitudinal axis defined by the upperchamber 102. The columnar portion 202 can be defined by an arcuateshaped outer wall 204 and the internal wall portion 150. The columnarportion 202 is further separated from the upper chamber interior volume170 by the internal wall portion 150 of the central portion 122. Thecolumnar portion 202 is in communication with the exit port 186 and theoutlet 200 and cooperates with the upper portion 120 and the lowerportion 124 to define a gas conduit 210 for gases of the dental officesuction exiting the upper chamber interior volume 170 through the exitport 186 to flow out of the outlet 200.

A flow path for liquids and solids of the dental office suction effluentare illustrated using arrows “A3” in FIGS. 1-3. The liquids and solidsof the dental office suction effluent travel along the substantiallycylindrical internal wall portion 150 of the central portion 122 of theupper chamber 102 and, predominantly by the force of gravity, flow intothe basin portion 156 of the lower portion 124.

The upper portion 120 and the lower portion 124 of the upper chamber 102can be formed of non-transparent or non-translucent materials. To complywith ISO standards, the central portion 122 is preferably formed oftransparent or translucent materials. As depicted in FIG. 2, the centralportion 122 is defined by the pair of stacked parts 140, 144, which canbe common shaped and sized parts 220. It should be appreciated that moreor less than the depicted number of parts 220 can be used to form thecentral portion 122. For example, a plurality of parts 220 can be formedand joined together intermediate the upper portion 120 and the lowerportion 124, if desired. It should be appreciated that the materialsutilized for the upper chamber 102 are polymeric in nature, and arejoined using conventional methods (e.g., adhesives and/or welding).

With reference to FIG. 3, the solids collection canister 110 includes atop portion 230 and a bottom portion 232. The bottom portion 232 canhave an outer circumference that is greater than an outer circumferenceof the top portion 230; although, this is not required. The top portion230 includes and upper end portion 236 releasably secured to the basinportion 156 of the upper chamber lower portion 124. In the depictedembodiment, a pair of circumferentially spaced fastening members 238which together with the bottom wall 160 of the basin portion 156 definea recess 240 dimensioned to receive the upper end portion 236 (see FIG.4). Once properly positioned opposed end portions of one fasteningmember 238 are connected to corresponding end portions of the otherfastening member 238 thereby securing the upper end portion 238 of thetop portion 230 to the basin portion 156. As best depicted in FIGS. 3and 5, the upper end portion 236 can include a circumferential groove246 dimensioned to receive a seal 248 (such as an O-ring) which providesa leak-tight connection between the upper chamber 102 and the solidscollection canister 110. Further, to provide for a compact apparatus100, a longitudinal axis defined by the solids collection canister 110can be aligned (i.e., coaxial) with the longitudinal axis of the upperchamber 102.

A lower end portion 250 of the top portion 230 is joined to an upper endportion 252 of the bottom portion 232 by a circumferential seam 256 todefine a solids collection canister interior volume 260. According toone aspect depicted in FIG. 3, the circumferential seam 256 is definedby a flange 262 located on the lower end portion 250 overlapping theupper end portion 252, which is located on the outside of the lower endportion 250. An adhesive can be applied to the circumferential seam 256(to define a glue joint) to permanently affix the top and bottomportions 230, 232 of the solids collection canister 110. FIG. 5illustrates an alternative configuration for the circumferential seam256′ between the top portion 230 and the bottom portion 232. It will beappreciated that other seam techniques could be utilized withoutdeparting from the invention.

As perhaps best illustrated in FIG. 5, the top portion 230 of the solidscollection canister 110 is provided with top wall 270 including a firstprojection 272 having a first opening 274 and a second projection 276having a second opening 278. The first opening 274 communicates with adrain 280 provided in the bottom wall 160 of the basin portion 156 ofthe upper chamber 102 (see FIG. 4). The second opening 278 communicateswith an inlet port 282 (which communicates with the outlet 200) alsoprovided in the bottom wall 160 of the basin portion 156 (see FIG. 4).In the assembled condition of the apparatus 100, the first projection272 is received in the drain 280 and the second projection 276 isreceived in the inlet port 282. To provide for a sealed connectionbetween these components, each of the first and second projections 272,276 includes a respective circumferential groove 286, 288 for receivinga respective seal (i.e.,OO-ring) 290, 292 (see FIG. 3).

The solids collection canister 110 further comprises a riser 300 thatconveys liquids and solids of the dental office suction effluent flowingfrom the upper chamber interior volume 170 through the drain 280 and thefirst opening 274 to the bottom portion 232 of the solids collectioncanister (see FIG. 5). According to one embodiment, the riser 300 is anelongated cylindrical shaped member having a longitudinal axissubstantially parallel to the longitudinal axis of the solids collectioncanister 110. According to one aspect, an upper end 302 of the riser 300is secured in a boss 304 depending from the top wall 270 of the topportion 230, the boss 304 having an axis that is coincident with an axisof the drain 280. A lower end 306 of the riser 300 includes a tipportion 310 having an exit opening 312. The tip portion 310 is shapedand configured to direct liquids and solids of the dental office suctioneffluent conveyed thereby toward an inner wall 316 of the bottom portion232 of the solids collection canister 110. According to one aspect, thetip portion 310 includes an inner surface 322 canted upwardly toward thetop wall 270 which directs liquids and solids of the dental officesuction effluent away from a flow restrictor 320.

As noted, the solids collection canister 110 further includes the flowrestrictor 320, which is mounted to and depends from the top wall 270 ofthe top portion 230. According to one aspect, the flow restrictor has anupper end 322 secured in a second boss 324 depending from the top wall270, the second boss 324 having an axis that is coincident with an axisof the inlet port 282. A cap 326 can be secured to a lower end 328 ofthe flow restrictor 320. The flow restrictor 320 is in fluidcommunication with the outlet 200 via the second opening 278 in the topportion 230 and a lower conduit 330 formed in the basin portion 156 ofthe lower portion 124 of the upper chamber 102 (see FIGS. 3 and 4). Thelower conduit 330 is in communication with the inlet port 282 and theoutlet 200 and extends in a direction substantially perpendicular to thelongitudinal axis of the upper chamber 102. The flow restrictor 320allows liquids and gases of the dental office suction effluent to exitthe solids collection canister interior volume 260, but prohibits solidsof the dental office suction effluent from exiting the solids collectioncanister interior volume 260. This can be accomplished through the useof a tubular element 336, which is provided with circumferential slits338 dimensioned to prevent the passage of solids larger than apredetermined size. Within the flow restrictor 320, a porous material(not shown) can be provided (e.g., sand media), which allows the passageof liquids and gases, but does not allow for the passage of solids.

With reference to FIG. 5, the inner wall 316 of the bottom portion 232of the solids collection canister 110 can be provided with a pluralityof upwardly extending flutes 350. Similarly, a bottom wall 352 of thebottom portion 232 can be provided with a plurality of flutes 354, whichcan be contiguous with the flutes 350. The flutes 350, 354 providestrength and also enhance separation of solids from liquids. The bottomwall 352 of the solids collection canister 110 can further include anindentation or punt 356, which encourages solids of the dental officesuction effluent to settle initially along a perimeter of the solidscollection canister interior volume 260. The punt 356 also makes it easyto hold and maintain the solids collection canister 110 in position withone hand with respect to the upper chamber 102 during removal andreplacement operations.

As indicated previously, in the depicted embodiment, the bottom portion232 of the solids collection canister 110 has an outer circumferencethat is greater than the outer circumference of the top portion 232.This allows the solids collection canister 110 to collect a largervolume (e.g., 1.5 L) of solids of the dental office suction effluentthan could otherwise be collected if the dimensions were the same or ifthe bottom portion 232 was smaller than the top portion 230. Thisconfiguration can be utilized as a replacement for solids collectionreceptacles on known amalgam separators, such as the HG5® unit presentlybeing sold by SolmeteX, Inc., which only are able to collect 1.0 L ofsolids. This reduces the frequency of canister changes. An outer ribbing360 can also be provided on the solids collection canister 110 toimprove its strength and also the ease by which it can be gripped (seeFIG. 1). It should be appreciated that the solids collection canister110 can be replaced once a predetermined volume (e.g., 1.5 L) of solidshas been collected therein.

FIG. 6A through FIG. 9 depict another embodiment of an apparatus 400 forremoving amalgam and waste particles from dental office suction effluentaccording to the present invention. The apparatus 400 has the samefunctionality and defines the same flow paths as the apparatus 100 shownin FIGS. 1-5, but includes additional features, which are discussed ingreater detail below.

As shown in FIGS. 6A-6D, the apparatus 400 generally comprises an upperchamber 402 having an upper end 404 and a lower end 406, and a solidscollection canister 410 removably secured to the lower end of the upperchamber. The upper chamber includes an upper portion 420, a centralportion 422, and a lower portion 424. The upper portion 420 includes anouter wall portion 426 having a first wall portion 428 and a second wallportion 430 projecting outwardly from the first wall portion 128.According to one aspect, the first wall portion 428 can be substantiallyhemispherical dome-shaped; although, this is not required.

With particular reference to FIGS. 7 and 9, the central portion 422includes a substantially cylindrical internal wall portion 440 adaptedto impart a circular flow to the dental office suction effluent beingdrawn into the upper chamber 402. The lower portion 424 of the upperchamber 402 includes a basin portion 442. The basin portion 442 isdefined by a vertical wall 444 and a bottom wall 446. The upper portion420, the substantially cylindrical internal wall portion 440 of thecentral portion 422 and the basin portion 446 of the lower portion 424cooperate to define an upper chamber interior volume 450.

The upper portion 420 and the lower portion 424 of the upper chamber 402can be formed of non-transparent or non-translucent materials. To complywith ISO standards, the central portion 422 is preferably formed oftransparent or translucent materials. It should be appreciated that thematerials utilized for the upper chamber 402 are polymeric in nature,and can be joined using conventional methods (e.g., adhesives and/orwelding). For example, as best depicted in FIGS. 7 and 9, one manner forconnecting the upper portion 420 to the central portion 422 and thecentral portion 422 to the lower portion 424 is to form grooves 452, 454at the peripheral edges of the central portion 422, which receivestraight peripheral edges of the upper and lower portions, respectively.This configuration improves the moldability of the parts, and ensures anaccurate seal between the portions 420, 422, 424 that comprise the upperchamber 402.

An inlet 460 is provided in the upper portion 420 of the upper chamber402 for establishing a connection to an inlet line (not shown) in fluidcommunication with at least one dental suction wand (not shown). Theinlet 460 is configured such that dental office suction effluent drawnthrough the at least one dental suction wand enters the upper portion420 of the upper chamber 402 along an initial lateral flow path into theupper portion 420 and then a circular flow path through the upperportion 420 above the internal wall portion 440 of the central portion422. Again, it should be appreciated that the use of the substantiallyhemispherical domed-shaped first wall portion 428 of the upper portionouter wall 426 allows the incoming dental office suction effluent toquickly change direction as it enters the upper portion 420 of theapparatus 400.

With reference to FIGS. 7-9, an exit port 466 is provided in the upperportion 420. The exit port 466 can be defined by the second wall portion430 of the upper portion 420 together with an internal divider 468formed in the upper portion 420 to separate the inlet 460 from the exitport 466. As depicted, the divider 468 includes a cylindrical section470 and a pair of curved sections 472, 474 extending from thecylindrical section and into engagement with an interface of the firstand second wall portions 428, 430 adjacent the inlet 460. The first wallportion 428 together with the divider 468 define a circular flow pathfor the dental office suction effluent being drawn into the upperportion 420 of the upper chamber 402. According to one aspect, the exitport 466 is so arranged such that gases of dental office suctioneffluent entering the upper chamber 402 through the inlet 460 has tochange direction by more than at least 50°, and more preferably at least60°, before gases can exit the upper chamber 402 through the exit port466. The dental office suction effluent is permitted to expand as itenters the upper portion 420 of the apparatus 400. The expansion and thechange of flow direction help separate gases from liquids and solids ofthe dental office suction effluent. The divider 468 defines anexpansion/deceleration zone 476 within the upper chamber interior volume450, which further assists in separating liquids and solids from theintake stream (see FIG. 7).

An outlet 480 is provided in the lower portion 424 for establishing aconnection to an outlet line (not shown) in fluid communication with avacuum pump (not shown). The central portion 422 includes a columnarportion 482 and the lower portion 426 includes a corresponding columnarportion 484. Each columnar portion 482, 484 has a longitudinal axissubstantially parallel to a longitudinal axis defined by the upperchamber 402. As best depicted in FIGS. 7 and 9, the columnar portion 482can be defined by an arcuate shaped outer wall 486 and the internal wallportion 440, which separates the columnar portion 482 from the upperchamber interior volume 450. The columnar portion 484 can be defined byan arcuate shaped outer wall 488 and the wall 444 of the basin portion442. Each columnar portion 482, 484 is in communication with the exitport 466 and the outlet 480 and cooperates with the upper portion 420and the lower portion 424 to define a gas conduit 490 for gases of thedental office suction exiting the interior volume 450 through the exitport 466 to flow out of the outlet 480. Similar to the function of theapparatus 100, liquids and solids of the dental office suction effluenttravel along the substantially cylindrical internal wall portion 440 ofthe central portion 422 of the upper chamber 402 and, predominantly bythe force of gravity, flow into the basin portion 446 of the lowerportion 424.

With reference to FIGS. 6A-6D, the solids collection canister 410includes a top portion 500 and a bottom portion 502. The bottom portion502 can have an outer circumference that is greater than an outercircumference of the top portion 500; although, this is not required.The top portion 500 includes and upper end portion 506 releasablysecured to the basin portion 442 of the upper chamber lower portion 424.As best depicted in FIGS. 7 and 9, the upper end portion 506 can includea circumferential groove 510 dimensioned to receive a seal 512 (such asan O-ring) which provides a leak-tight connection between the upperchamber 402 and the solids collection canister 410. To provide for acompact apparatus 400, a longitudinal axis defined by the solidscollection canister 410 can be aligned (i.e., coaxial) with thelongitudinal axis of the upper chamber 402. A lower end portion 516 ofthe top portion 230 is joined to an upper end portion 518 of the bottomportion 502 by a circumferential seam 520 to define a solids collectioncanister interior volume 524. An adhesive can be applied to thecircumferential seam 520 to permanently affix the top and bottomportions 500, 502. Again, it will be appreciated that other seamtechniques could be utilized without departing from the invention.

With continued reference to FIGS. 7 and 9, the top portion 500 of thesolids collection canister 410 is provided with top wall 530 including afirst projection 532 having a first opening 534 and a second projection536 having a second opening 538. The first opening 534 communicates witha drain 540 provided in the bottom wall 446 of the basin portion 442 ofthe upper chamber 402. The second opening 538 communicates with an inletport 542 also provided in the bottom wall 446 of the basin portion 442.In the assembled condition of the apparatus 400, the first projection532 is received in the drain 540 and the second projection 536 isreceived in the inlet port 542. To provide for a sealed connection, eachof the first and second projections 532, 536 can include acircumferential groove for receiving a seal (i.e., O-ring) (see FIG. 9).

The solids collection canister 410 further comprises a riser 550 mountto and depending from the top wall 446 that conveys liquids and solidsof the dental office suction effluent flowing from the upper chamberinterior volume 450 through the drain 540 and the first opening 534 tothe bottom portion 502 of the solids collection canister 410. The riser550 is shaped and configured similar to riser 300, and the manner forsecuring the riser 550 to the top wall 446 is similar to the connectionof the riser 300 to the top wall 270. Therefore, further description ofthese features of the apparatus 400 is omitted for conciseness.

A flow restrictor 560 is mounted to and depends from the top wall 446.Because the manner for securing the flow restrictor 560 to the top wall446 is similar to the connection of the flow restrictor 320 to the topwall 270, further description of these features of the apparatus 400will be omitted for conciseness. The flow restrictor 560 is in fluidcommunication with the outlet 480 via the second opening 538 in the topportion 500 and a lower conduit 570 formed in the basin portion 442 ofthe lower portion 424 of the upper chamber 402 (see FIGS. 7 and 9). Thelower conduit 570 is in communication with the inlet port 542 and theoutlet 480 and extends in a direction substantially perpendicular to thelongitud°inal axis of the upper chamber 402. The flow restrictor 560allows liquids and gases of the dental office suction effluent to exitthe solids collection canister interior volume 524, but prohibits solidsof the dental office suction effluent from exiting the solids collectioncanister interior volume 524.

In the depicted embodiment, the flow restrictor 560 can be formed of aninert micro-fiberglass material bonded with a stable resin, randomly setinto a multi-layer composite. In the present embodiment of theinvention, the material of the flow restrictor 560 has a 3 micronabsolute rating. In the illustrated flow restrictor 560, the fiberglassmaterial is co-pleated with inner and outer support layers, which can bemade of corrosion resistant materials such as metal (stainless steel)and/or plastic. It is important that the material, at gravity feed, havea low pressure differential across the separation media. Use of a flowrestrictor having a configuration as described should improve theseparation efficiency of the amalgam separator apparatus 400substantially, with amalgam particle separation efficiencies of 99% orgreater being expected in accordance with testing under the ISO11143:2008 standard.

With reference to FIG. 9, an inner wall 576 of the bottom portion 502 ofthe solids collection canister 410 can be provided with a plurality ofupwardly extending flutes 580. Similarly, a bottom wall 582 of thebottom portion 502 can be provided with a plurality of flutes 584, whichcan be contiguous with the flutes 580. The flutes 580, 584 providestrength and also enhance separation of solids from liquids. The bottomwall 582 of the solids collection canister 410 can further include anindentation or punt 586, which encourages solids of the dental officesuction effluent to settle initially along a perimeter of the solidscollection canister interior volume 524.

FIG. 8 depicts mounts 590, which are formed in the upper portion 420.The mounts 590 can be connected to brackets or hardware (not shown)allowing the upper chamber 402 to be fixedly mounted to a wall or otherlocation. It will be appreciated that the location and configuration ofthe mounts 590 is not per se critical, and that a variety of differentmounting arrangements could be used.

In its broadest sense, an exemplary method for removing amalgam andwaste particles from dental office suction effluent comprises providingan apparatus as disclosed herein, and suctioning waste from a patient'smouth through a dental office suction effluent wand in fluidcommunication with the apparatus. Once the interior volume of the solidscollection canister has been sufficiently filled with solid particles(e.g., 1.5 L), the entire solids collection canister is removed from theupper chamber, and a new solids collection canister is secured to theupper chamber in its place. The solids collection canister filled withcollected solids can be packed and shipped to a recycling facility,where the metals are recovered.

According to one aspect, a method for removing amalgam and wasteparticles from dental office suction effluent comprises imparting acircular flow path to a dental office suction effluent entering an upperseparation chamber of a separation apparatus; separating gases from thedental office suction effluent and discharging the separated gases fromthe upper separation chamber; directing the dental office suctioneffluent into a solids collection canister removably secured to a lowerend of the upper chamber via a riser located in the solids collectioncanister; separating solids from the dental office suction effluent inthe solids collection canister; and discharging liquids and gases of thedental office suction effluent through a flow restrictor located in thesolids collection canister. The method can further comprise dischargingthe separated gases through a separate gas conduit provided in the upperchamber. The method can further comprise conveying liquids and solids ofthe dental office suction effluent flowing from the upper chamber towardan inner wall of the solids collection canister.

The device and method are preferably capable of handling an effluentflow rate of at least one 1 L per minute. The flow rate of effluent isprimarily governed by the flow restrictor. The amount of effluentflowing into the device will vary depending upon the number of chairs inuse. When the effluent inflow temporarily exceeds the maximum flow rate,the effluent will accumulate in the upper chamber, and then graduallydrain off through the solids collection canister when inflow ratesdiminish. Thus, the device can be used in conjunction with multipledental chairs simultaneously.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and illustrative examples shown anddescribed herein. Accordingly, various modifications may be made withoutdeparting from the spirit or scope of the general inventive concept asdefined by the appended claims and their equivalents.

1. An apparatus for collecting amalgam from dental office suctioneffluent, the apparatus comprising: an upper chamber having a top, ahollow central portion, and a bottom, the top and bottom closing off thehollow central portion to define an upper chamber interior volume; aninlet provided in the top of the upper chamber for receiving dentaloffice suction effluent from at least one dental suction wand in fluidcommunication with the inlet; a gas conduit within the upper chamberinterior volume, the gas conduit having an upper opening that defines anexit port; an outlet extending from the upper chamber for establishing aconnection to an outlet line in fluid communication with a vacuum pump,wherein a lower end of the gas conduit is in fluid communication withthe outlet; a solids collection canister removably secured to the bottomof the upper chamber, the solids collection canister including a topportion and a bottom portion which together define a solids collectioncanister interior volume, the top portion of the solids collectioncanister being provided with a first opening and a second opening, thefirst opening communicating with a drain provided in the bottom of theupper chamber, the second opening communicating with the outlet; and aflow restrictor disposed in the solids collection canister interiorvolume, the flow restrictor allowing liquids and gases of dental officesuction effluent passing from the upper chamber into the solidscontainer through the drain to exit the solids collection canisterthrough the second opening as amalgam in the dental office suctioneffluent that enters the solid collection canister through the drain iscollected and retained in an interior volume of the solids collectioncanister.
 2. The apparatus of claim 1, wherein there are no otheropenings in the top of the upper chamber aside from the inlet.
 3. Theapparatus of claim 1, wherein the hollow central portion comprises asubstantially cylindrical internal wall portion.
 4. The apparatus ofclaim 3, wherein the inlet is shaped and configured such that dentaloffice suction effluent drawn through the at least one dental suctionwand enters the upper chamber along a lateral flow path above thesubstantially cylindrical internal wall portion of the hollow centralportion, the lateral flow path being substantially perpendicular to alongitudinal axis defined by the upper chamber.
 5. The apparatus ofclaim 3, wherein the substantially cylindrical internal wall portion ofthe hollow central portion is adapted to impart a circular flow path tothe dental office suction effluent.
 6. The apparatus of claim 1, whereinthe exit port is arranged such that a flow of gases of dental officesuction effluent entering the upper chamber through the inlet changesdirection by more than 60° before the gases exit the upper chamberthrough the exit port.
 7. The apparatus of claim 1, further comprising ariser in communication with the first opening of the solids collectioncanister, the riser adapted to convey liquids and solids of the dentaloffice suction effluent flowing from the upper chamber interior volumethrough the drain and the first opening to the bottom portion of thesolids collection canister.
 8. The apparatus of claim 7, wherein theriser comprises an elongated cylindrical shaped member having alongitudinal axis substantially parallel to a longitudinal axis of thesolids collection canister.
 9. The apparatus of claim 7 wherein theriser includes a tip portion having an exit opening, the tip portionbeing adapted to direct liquids and solids of dental office suctioneffluent conveyed thereby toward an inner wall of the bottom portion ofthe solids collection canister.
 10. The apparatus of claim 9, whereinthe tip portion includes a surface canted upwardly toward the topportion of the solids collection canister.
 11. The apparatus of claim 1,wherein the flow restrictor is mounted to and depends from the topportion of the solids collection canister, the flow restrictor being influid communication with the outlet.
 12. The apparatus of claim 10,wherein a lower conduit is formed in the bottom of the upper chamber,the lower conduit being in fluid communication with the second openingof the solids collection canister and the flow restrictor.
 13. Theapparatus of claim 1, wherein the top portion and the bottom portion ofthe solids collection canister are joined together by a circumferentialseam.
 14. The apparatus of claim 1, wherein the bottom portion of thesolids collection canister has an outer circumference that is greaterthan an outer circumference of the top portion of the solids collectioncanister.
 15. The apparatus of claim 1, wherein the flow restrictor isformed of an inert micro-fiberglass material bonded with a stable resin,randomly set into a multi-layer composite.
 16. A method for removingamalgam and waste particles from dental office suction effluent, themethod comprising: imparting a circular flow path to a dental officesuction effluent entering an upper separation chamber of a separationapparatus separating gases from the dental office suction effluent anddischarging the separated gases from the upper separation chamberthrough a gas conduit provided in the upper chamber; directing thedental office suction effluent into a solids collection canisterremovably secured to a lower end of the upper chamber; separating solidsfrom the dental office suction effluent in the solids collectioncanister; and discharging liquids and gases of the dental office suctioneffluent through a flow restrictor located in the solids collectioncanister.
 17. The method of claim 16, wherein the dental office suctioneffluent is directed into the solids collection canister via a riserlocated in the solids collection canister.
 18. The method of claim 16,further comprising conveying liquids and solids of the dental officesuction effluent flowing from the upper chamber toward an inner wall ofthe solids collection canister.
 19. The method of claim 17, wherein theriser comprises an elongated cylindrical shaped member having alongitudinal axis substantially parallel to a longitudinal axis of thesolids collection canister.